MELBOURNE (Reuters):

NEVER one to do things by the book, Serena Williams dramatically tore up the script on Friday night (Ja time) to bring top seed Maria Sharapova to her knees and capture a third Australian Open crown.

Comeback queen Williams demonstrated that she still belonged among the elite as she annihilated Sharapova 6-1, 6-2 to win her eighth grand slam trophy.

The American had entered the tournament ranked 81st in the world, but made it look like a mathematical error with her brutal 63-minute destruction of a shell-shocked Sharapova.

Down on bended knee, Williams fired a crunching backhand angled winner to seal the match and immediately sent her racquet flying out of her hand as she fell flat on her back in her moment of triumph.

Holding her head in her hands in disbelief, she got back on her feet and began leaping around the court. In fact she could barely stand still as she performed an impromptu jig before mouthing the words "Hey dad, thanks for the advice".

Dedicated win to sister

But once she hugged the trophy the tears started rolling down her cheeks as she dedicated the win to her sister who was shot dead in Los Angeles in 2003.

"I would like to dedicate this win to my sister, who is not here, her name is Yetunde," Williams said her voice cracking with emotion. "I just love her so much. A couple of days ago, I said if I win this it will be for her, so thanks Yetunde," added Williams, who will climb to 14th in the world tomorrow.

Williams had proved she still possessed an appetite for winning big titles by trampling over five seeds in the run up to the final. On Friday night she claimed the biggest one of them all.

She become the third lowest-ranked woman to win a major since the inception of rankings and only the second unseeded woman to win the Australian crown in the professional era after Chris O'Neil achieved the feat in 1978.

It was the most lopsided women's final here since Steffi Graf beat Arantxa Sanchez-Vicario for the loss of just two games in 1994.

"You can never under-estimate her, not many people expected her to reach the final but I did, she's an amazing champion," said Sharapova, who was looking to become the first Russian woman to win in Melbourne. "I look forward to playing here many more times and winning a few more games I hope."

Two weeks ago, no one gave Williams a chance to reach the second week, let alone the final. She played only 16 matches in 2006. Until arriving in Hobart earlier this month, no one had seen her on a tennis court for four months as she recuperated from yet another injury.

Her trophy cabinet had not had any new additions since she won the last of her titles in Melbourne Park two years ago.

Even Williams had acknowledged: "I don't think anyone thought I would get this far, except me and my mom." She and her mom proved to be astute soothsayers.

Crowd on her side

Just as Goran Ivanisevic had defied the odds to win the 2001 Wimbledon crown ranked 125th in the world, Serena earned her place alongside some of tennis's most memorable comeback artists.

"When I'm playing well, it's difficult for anyone to beat me, because I have a unique style. Tennis is what I was born to do," said the 25-year-old.

While Sharapova was the bookmakers' favourite for the title, Williams had the crowd on her side.

Her steely temperament was on show from the start as she left Sharapova reeling by ominously charging to a 5-0 lead.

The Russian looked like her feet had been super-glued to the Rebound Ace surface as she failed to produce a winner until the sixth game of the first set.

When she did, she smashed the ball straight into Williams's body. A fired-up Williams warned: "You'll pay for that."

She was true to her word. The Russian, who had come within two points of defeat in her opening match, changed her racquet after being broken in the first game of the second set, but to little avail.